Wednesday, November 17, 2010

Capsize

rev. 11-20-2010

Shoal Survivor is tied safely to a dock in Deale, not to worry. Today's gale warnings helped me think of a worthwhile post. I thought it over some more while I collected lawn furniture and trash cans from all over the neighborhood.

I have no intention of flogging a dead horse. Many of the readers of this blog have cats and they know the score. I've sailed them for 25 years and I've pitch-poled and capsized performance cats in the most dramatic fashion--beach cats, not cruisers. I've been thrown 20 feet in front of the boat, launched from the trapeze, and come up laughing.

I sailed a Stiletto 27 for 16 years, a boat that bridges the gap between beach cat and cruising boat. We hit 20 knots on several occasions and double digits every month. We flew a hull clear of the water now and then, but always in controlled conditions. They've been flipped numerous times, by skippers pushing the envelope or simply not paying attention. They're light, quite over canvased... and fun.

My PDQ 32 has never given me reason to think about capsize. The "theoretical" limit has been calculated at 35 knots apparent with self tacking jib and main and I can't imagine having everything up and tightly sheeted in that. With genoa and main she can start getting a little light at 25 knots and would probably consider going over at 32 knots apparent, but that's only my guess. That should leave plenty of time to make reductions or at least free a sheet. In reality, reefing begins no later than 25 knots apparent in the gusts--catamarans always reef for the gusts--since the boat is going recklessly fast and is poorly balanced by then. Thunderstorms and big waves bear watching.

Presented below are two tales of PDQ32s that did not reduce in time or take appropriate steps. There are lessons to be learned, to be sure, but also the reassurance, that you have to do something monumental thick to get in that much trouble: in one case the solo sailor was down below in 40 knots winds, and in the other they left harbor with a 50 knot gale predicted.

Let's focus on not being too thick, because s_ _t happens when we're tired or read too many tales of daring do.

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PDQ 32 capsizing while entering a cut in the Bahamas while a "rage" was blowing. Pitchpoled in very shallow water in the huge breakers

(reported 2005 by Capt. JG)

I talked at length to the owner of this boat shortly after the episode. Apparently, the charterer was singlehanding, on autopilot, and down below. He was carrying full sail (one report said one turn on the jib) in 25+ knots, sheeted in tight, while on a beam reach. He was not entering, but passing by a notoriously windy cut in the Abacos (by Whale Cay?) and got hit by an estimated 45 knot gust and 6 foot wave beam on. The boat did not pitchpole, but slowly went on its side, and stayed there for several hours while the owner (who came from Marsh Harbor?) and others tried to right it. Finally, a stay broke and it capsized. It was towed back to Marsh Harbor where the deck was trashed by efforts to lift it inverted with slings. I saw the boat in Toronto awaiting a deck rebuild.

One design factor considered by cat builders is how much wind could a boat handle in such a worst case of gust on the beam with full sail sheeted in. The figure used for the PDQ 32 is 45 knots. The assumption is that in almost all cases where 45 knots is possible, you would shorten sail--even a single reef makes a huge difference in this situation. Also, in most cases someone would be on deck to release asap. A significant lesson is that whenever full sail is sheeted in during a blow, someone must be on deck!

Two other factors apply here: First, this particular boat was sailing "light." That is, it was stripped out and not carrying cruising gear. If it were loaded, it probably would not have gone over. The second is that this design has a rather narrow beam, coupled with a tall profile. This is one of the issues with smaller cats, since the temptation by designers is to make them narrow enough for a slip. Also, since the bridge deck clearance and overhead boom height have practical minimums, smaller cats have proportionally taller rigs. The combination of narrow beam and tall rig makes this sort of incident inevitable. For this reason, I've usually said that the minimum size for an offshore capable cat is about 35 feet, unless it has a very conservative rig.

PDQ Capsizes in 50 knot Winds Off California Coast

This incident was on all the nets this summer. In a nutshell, an inexperienced crew took a new-to-them boat out in the face of a horrible weather forecast and got stomped. The conditions would have stomped many boats, but I'm sure their inexperience with this boat and sailing cats in general was important too. I can't imagine taking on the weather they faced on their delivery trip; I would have waited as long as I needed for a better window. I seems they had only a few days of vacation available....

Of course, both boats were recovered and rebuilt. No one was physically injured, but pride and confidence must have taken a pounding. My pride would be mortally wounded after such experiences, and complete healing might never come, from a wound so deep. Not fear--I've had too many adventures to the edge--but embarrassment at my hubris, that I had thought I was safe and was dead wrong. My ability to calculate the edge of safety and my confidence in those calculations, my right to bring others into my adventures, and my pride in seamanship would be forever forfeit.

I've sailed cats for many years, and that has made me a coward in many ways. I reef while I can still do so safely, I stay on deck when it's anything but calm, and I will always remember what a beach cat feels like when things are about to get crazy.

Regrettably, I like that feeling...!

1. Winches should ALWAYS be ready for release in gusty conditions. Only 2 wraps on the winch to reduce the chance of over-rides and the tail in a cam cleat rather than the self-tailer.

2. Each sheet should be on its own winch. No jammers locked. There are a few cats out there that don't have enough winches to dedicate one to each sail; they must leave one in a jammer. This is cheap boat-show design and a winch should be added.

3. Sheets must be releasable by the helmsman AND releasable by a crew member. The best way in a real breeze is for a crewman to sit by the winch with the tail in his hands, across his lap.

4. If the bows are starting to go under (more than spray or an occasional wave top), reduce sail dramatically. If the tramp buries, the boat will stop fast, and that momentum can lead to capsize and pitchpole (often the line between these is gray)

One thing I did on my boat early on--I didn't notice if yours was this way--was to add 2 cam cleats on starboard and one on port. When it is really blowing or gusty, I take the sheet out of the self-tailer, unwind until there are only 2 turns on the winch, place the sheet in the cam cleat, and make sure it is where I can get to it for instant release. More than 2 turns on a winch promises an override, and the self-tailer takes time.

Keeping a Cruising Boat for Peanuts--Available in PDF!

As much as I love sailing, putting my daughter through college and funding my 401K are more important. Transitioning from professional engineer to writer has transformed my habit of living efficiently into a passion for spreading funds thin. I like to think of it as a challenge for the imagination—it’s more fun that way.

I’ve written over 100 equipment reviews and engineering articles for popular sailing magazines, all based on laboratory and hands-on testing. I’ve spent 30 years learning how to maintain, fix, and upgrade. I've also spent 35 years as a chemical engineer, and my wife thinks I live in my basement shop.

As a result I’ve become a fair hand most crafts, never get stuck in the field with something I can’t fix, and I've learned to spread money thin, without compromising speed, reliability, or performance. Although I've written on many topics, my wife assures me this is the one I know best. My magnum opus?

About Me

This is my place to share my enthusiasm for the Chesapeake Bay, Delmarva Peninsula, PDQ And Corsair F-24 specific minutia, and sailing in general. As a regular contributor to sailing magazines including Practical Sailor and Good Old Boat (over 150 articles), it provides a place to try out ideas and publish the overflow. Here I can blurt it out half formed ideas, collect comments, and to see what questions my inquiry suggests. If I need to get long winded or philosophical, it’s my space to do so.
After 15 years of kayaking, 35 years of sailing, 35 years of rock and ice climbing, and 40 years as a chemical engineer, I still have much to learn and my life is still one giant science project. My end of the pier is always festooned with test rigs and warning signs. Every research project brings surprises—things I didn’t know, and just as often, things no one knew. And so through books and articles, I share.